JPH093124A - Modified amorphous polyolefin and its continuous production - Google Patents

Abstract

PURPOSE: To obtain a modified amorphous polyolefin improved in flexibility, bondability, toughness, etc., by grafting an unsaturated carboxylic acid onto an amorphous polyolefin in the presence of an organic peroxide in an extruder to form an acid-modified amorphous polyolefin and neutralizing the product with a metal compound. CONSTITUTION: An unsaturated carboxylic acid (anhydride) is grafted onto a polymer (A) containing at least 50mol % 3-8C α-polyolefin in the presence of an organic peroxide in an extruder to obtain an acid-modified polyolefin. The product is partially or perfectly neutralized with an ionic metal compound (C) to obtain a modified amorphous polyolefin. The component A is particularly desirably a propylene (co)polymer having a number-average molecular weight of 3,000-30,000. The acid (anhydride) B is desirably of 4-8 carbon atoms and is exemplified by acrylic acid or maleic acid. The acid (anhydride) B is used in such an amount that the acid value of the obtained acid-modified amorphous polyolefin is 1-400mgKOH/g. The compound C is desirably a formate, oxide, hydroxide, methoxide, carbonate or the like of Na<+> , Mg<++> or Zn<++> .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel modified amorphous polyolefin, more specifically, a packaging material, a molding processed material, which has excellent adhesiveness, toughness, heat resistance and pinhole resistance, The present invention relates to a modified amorphous polyolefin that can be widely used as an adhesive and a modifier for various resins.

[0002]

PRIOR ART AND PROBLEMS TO BE SOLVED BY THE INVENTION α-
An unsaturated dicarboxylic acid anhydride is graft-copolymerized on an ethylene / α-olefin copolymer rubber having an olefin content of 20 to 40 mol%, and then the dicarboxylic acid anhydride group is partially neutralized with sodium ion or potassium ion. It is known that by doing so, the tensile strength, permanent elongation and the like are improved (Japanese Patent Publication No. 62-17602).
On the other hand, a graft copolymer of an unsaturated carboxylic acid derivative onto a specific amorphous low molecular weight polyolefin is disclosed in JP-A-1-28.
No. 2207, the carboxylic acid groups and / or carboxylic acid anhydride groups of the graft copolymer are further neutralized with metal ions, but they are not yet known.
That is, in JP-A-1-282207, an amorphous low molecular weight propylene-ethylene having a propylene component of 71 to 95 mol%, an ethylene component of 29 to 5 mol% and a number average molecular weight of 3,500 to 30,000. The unsaturated carboxylic acid derivative component consisting of an unsaturated carboxylic acid having 3 to 10 carbon atoms, its acid anhydride and its ester is graft-copolymerized to the copolymer in an amount of 0.1 to 40 parts by weight per 100 parts by weight of the polymer. It is only described that it can be used as a modifier for various resins or as a resin having excellent adhesiveness, printability and dyeability. By the way, 50 mol% of the above-mentioned α-olefin having 3 to 8 carbon atoms is used.
The amorphous low molecular weight polyolefin contained above is often used as a main raw material of a soft hot melt adhesive. Although the above-mentioned graft copolymer is certainly sufficiently modified in terms of improving the adhesiveness, it is required to have toughness and heat resistance in addition to the characteristics of flexibility and adhesiveness. Therefore, the object of the present invention is to widely use it as a packaging material excellent in flexibility, adhesiveness, toughness, heat resistance, and pinhole resistance, a molding material, an adhesive, and a modifier for various resins. It is to provide a modified amorphous polyolefin that can be obtained.

[0003]

As a result of intensive studies, the present inventors have found that the carboxylic acid groups and / or carboxylic acid anhydride groups of the acid-modified amorphous polyolefin are partially or completely ionic metal compounds. It has been found that a polymer neutralized to achieve the above object.

Hereinafter, the present invention will be described in detail. The amorphous polyolefin of the acid-modified amorphous polyolefin in the present invention is a homopolymer, a binary copolymer, or a multicomponent copolymer containing 50 mol% or more of an α-olefin having 3 to 8 carbon atoms. Particularly preferably, propylene homopolymer, propylene / ethylene copolymer, propylene / butene-1 copolymer, butene-1 / ethylene copolymer, propylene / hexene-1 copolymer, propylene-4-methyl- Pentene-1 copolymer, butene-1 / hexene-
1 copolymer, propylene / ethylene / butene-1 terpolymer, propylene / ethylene / hexene-1 terpolymer, propylene / ethylene-4-methyl-pentene-
1 terpolymer, propylene butene-1 hexene-
1 terpolymer, propylene / hexene-1 / octene-1 terpolymer, propylene / hexene-1 / 4-methyl-pentene-1 terpolymer or other propylene component or butene-1 component Amorphous polyolefin as the main component can be used.

As an amorphous polypropylene,
Atactic polypropylene produced as a by-product during the production of crystalline polypropylene may be used, or it may be produced directly from a propylene raw material. In addition, propylene or butene
The copolymer of 1 with other α-olefin can be produced by using the raw material so as to contain a predetermined propylene or butene-1 component. In the case of such production, it can be obtained, for example, by polymerizing a raw material monomer in the presence or absence of hydrogen using a titanium-supported catalyst supported on magnesium chloride and triethylaluminum. From the viewpoint of supply stability and quality stability, it is desirable to use the objectively produced amorphous polyolefin. Further, a suitable and suitable commercial product can be appropriately selected and used. The amorphous polyolefin preferably has a heat of crystal fusion of 20 Joule / g or less. If the heat of fusion of crystals is out of the above range, the modified product of the present invention is unfavorable because the flexibility near room temperature is poor.

The heat of crystal fusion was measured as follows. That is, this heat of crystal fusion is a value calculated using a straight line obtained by directly extrapolating the specific heat curve of the polymer in a completely molten state by a differential scanning calorimeter to the low temperature side as a baseline. The measurement was carried out using a DSC-50 manufactured by Shimadzu Corporation as a differential scanning calorimeter, and the sample amount was about 10 m.
g, a nitrogen atmosphere was used as a measurement atmosphere, and indium was used as a heat quantity standard. The heating program was as follows. That is, the sample was heated to 210 ° C. at a heating rate of 50 ° C./min, left at 210 ° C. for 5 minutes,
Cool to -42 ° C at 10 ° C / min cooling rate, -42 ° C
Let stand for 5 minutes. After that, at a temperature rising rate of 20 ° C / min, -4
The measurement was performed from 0 ° C to 200 ° C.

The amorphous polyolefin has a number average molecular weight of 2,000 to 40,000, preferably 3,0.
00 to 30,000. Number average molecular weight of 2,000
If it is less than the above range, the property as a polymer is not exhibited, and the modified product of the present invention lacks toughness. Further, if the number average molecular weight exceeds 40,000, the modified product of the present invention is not preferable because the flexibility and adhesiveness at around room temperature are poor. The number average molecular weight can be measured by a known method such as gel permeation chromatography (GPC).

Further, the amorphous polyolefin has a boiling n-heptane insoluble content, that is, a Soxhlet extraction insoluble content by boiling n-heptane of 70% by weight or less, preferably 60% by weight or less, particularly preferably 10% by weight or less. Things are desirable. When the boiling n-heptane insoluble content is more than 70% by weight, the ratio of the amorphous portion is small and the modified product of the present invention cannot obtain sufficient flexibility at around room temperature.

The acid-modified amorphous polyolefin of the present invention is
Unsaturated carboxylic acid and / or
Alternatively, the acid anhydride is graft-copolymerized.
The unsaturated carboxylic acid and / or its acid anhydride has a carbon number in the range of 3 to 10, and more preferably 4 to 8. When the number of carbon atoms is less than 3, odor is strongly attached to the polymer, and when the number of carbon atoms exceeds 10, the graft reaction is unlikely to occur. Examples of the unsaturated carboxylic acid having 3 to 10 carbon atoms and / or its acid anhydride include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, tetrahydrophthalic acid, bicyclo (2,2,2). 1) Unsaturated carboxylic acids such as hept-2-ene-5,6-dicarboxylic acid, maleic anhydride, itaconic anhydride, citraconic anhydride, tetrahydrophthalic anhydride, bicyclo (2,2)
2,1) anhydrides of unsaturated carboxylic acids such as hept-2-ene-5,6-dicarboxylic acid anhydride.

The graft copolymerization is carried out by a known method. For example, organic peroxide is added to a molten mixture of amorphous polyolefin and unsaturated carboxylic acid and / or its acid anhydride, or to a solution using a solvent such as toluene or xylene. Further, ionizing radiation such as γ-rays may be irradiated without adding the organic peroxide. In any case, it is preferable to avoid mixing of air and oxygen in this graft copolymerization, and it is desirable to carry out in an atmosphere of an inert gas such as nitrogen gas or carbon dioxide gas.

The organic peroxide preferably has a decomposition temperature in the range of 70 to 270 ° C., which has a half-life of 1 minute, and includes, for example, acetylcyclohexylsulfonyl peroxide, benzoyl peroxide, dichlorobenzoyl peroxide, dicumyl peroxide. , The -tert-
Butyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexyne-3,1,4
-Bis (tert-butylperoxyisopropyl) benzene, lauroyl peroxide, tert-butylperoxyacetate, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, tert-
Butyl peroxybenzoate, tert-butyl peroxylaurate, tert-butyl peroxyisobutyrate, tert-butyl peroxypivalate, cumyl peroxy octoate, tert-butyl peroxy (2-ethylhexanoate), tert-butyl hydroperoxide , Tert-butyl peroxyisopropyl monocarbonate, cumene hydroperoxide and the like.

The graft copolymerization temperature when an organic peroxide is used depends on the softening point of the amorphous polyolefin and the decomposition temperature of the organic peroxide, but is generally 80 to 300 ° C.

Amount of unsaturated carboxylic acid and / or its acid anhydride and organic peroxide compounded, temperature of graft copolymerization
The acid value of the obtained acid-modified amorphous polyolefin is 1 to 400 mg KOH / g, preferably 1 to 200 mg
It is appropriately selected to be KOH / g. Here, the acid value is the number of mg of KOH required for neutralization per 1 g of the polymer, and in this case, it is a measure of the concentration of carboxylic acid groups and / or carboxylic acid anhydride groups in the acid-modified amorphous polyolefin. Equivalent to. When the acid value of the acid-modified amorphous polyolefin is less than 1, the polarity is insufficient and the modified product of the present invention does not exhibit adhesiveness. Further, if it is attempted to obtain more than 400, side reactions such as main chain cleavage or cross-linking of the amorphous polyolefin will not occur and effective modification will not occur, so that more than 400 is practically not preferable.
Of course, as the acid-modified amorphous polyolefin of the present invention, a suitable commercial product can be appropriately selected and used.

The modified amorphous polyolefin of the present invention is obtained by partially or completely neutralizing the carboxylic acid groups and / or carboxylic acid anhydride groups of the acid-modified amorphous polyolefin with an ionic metal compound. can get. The ionic metal compound of the present invention is selected from compounds of metals having a valence of 1 to 3 in Group I, II, III, IV-A and VIII of the periodic table. Of these, preferred compounds are formates, acetates, oxides, hydroxides, methoxides, ethoxides, carbonates and bicarbonates. Suitable metal ions are Na ⁺ , K ⁺ , Ca ⁺⁺ , Mg ⁺⁺ , Zn ⁺⁺ , B.
a ⁺⁺ , Fe ⁺⁺ , Co ⁺⁺ , Ni ⁺⁺ , Fe ⁺⁺⁺ , and Al
It is ⁺⁺⁺ . Of these, Na ⁺ , Mg ⁺⁺ and Zn ⁺⁺ are effectively used. These various ionic metal compounds can be used in combination as required.

The carboxylic acid group and / or carboxylic acid anhydride group of the acid-modified amorphous polyolefin is neutralized by the ionic metal compound, and the carboxylic acid group and / or carboxylic acid anhydride group is neutralized. The degree is 10% or more. When the degree of neutralization is less than 10%, the modified product of the present invention does not exhibit toughness and heat resistance. Therefore,
Type and amount of the ionic metal compound, temperature of neutralization reaction
The time is appropriately selected so that the degree of neutralization is 10% or more. The degree of neutralization can be measured from the characteristic absorption based on the carboxylate metal ion salt in the infrared absorption spectrum. The neutralization reaction needs to be carried out under conditions such that the ionic metal compound is uniformly dispersed in the acid-modified amorphous polyolefin. In addition, it is necessary to take measures to easily remove by-products generated by neutralization. For this reason, it is generally desirable to carry out melt mixing of the acid-modified amorphous polyolefin and the ionic metal compound at a temperature of 350 ° C. or lower. Also,
It is also possible to neutralize in a solution state using a solvent.

An extruder is preferably used for industrially producing the modified amorphous polyolefin of the present invention.
A single-screw or multi-screw extruder with a vent can be used as the extruder. In this case, if there is a suitable acid-modified amorphous polyolefin in advance, it may be directly supplied to the extruder and melt-kneaded with the ionic metal compound. Further, as described below, the amorphous polyolefin is acid-modified in an extruder,
Subsequently, this may be melt-kneaded with the ionic metal compound in an extruder.

(Acid modification step) Amorphous polyolefin, organic peroxide, unsaturated carboxylic acid and / or acid anhydride thereof are simultaneously or simultaneously fed from a hopper or a vent using a plurality of twin-screw extruders with vents. Add separately. The cylinder temperature is determined by the softening point of the amorphous polyolefin and the decomposition temperature of the organic peroxide. Generally, the temperature is 80 to 220 ° C., and the graft copolymerization is almost completed by the melt kneading for 20 seconds to several minutes.

In general, amorphous polyolefin has a strong adhesive property and is difficult to be pelletized, so that it cannot be directly charged from a hopper. Therefore, it is preferable to heat and melt and supply from a hopper or a vent port with a metering pump. At this time, the melting and supplying temperature is preferably 20 ° C. or higher, more preferably about 120 to 220 ° C., from the softening point of the amorphous polyolefin. Further, in this case, the unsaturated carboxylic acid and / or its acid anhydride is, for example, maleic anhydride (melting point 53 ° C.,
(White flakes or granules at room temperature with boiling point of 202 ℃)
However, since sublimation becomes remarkable at high temperature, it is preferable to avoid blending with the molten amorphous polyolefin and supply it from C ₀ to C ₁ separately from the molten amorphous polyolefin.

The organic peroxide is selected according to the softening point of the amorphous polyolefin used. Since the decomposition half-life of the organic peroxide has a value determined by the temperature, when graft-copolymerizing with an amorphous polyolefin having a low softening point, an organic peroxide having a low decomposition half-life temperature, for example, ter
t-butylperoxy (2-ethylhexanoate)
[Perbutyl O, manufactured by NOF CORPORATION, decomposition half-life 1 minute temperature: 135 ° C.] is also used in the case of graft copolymerization with an amorphous polyolefin having a high softening point, an organic peroxide having a high decomposition half-life temperature. An oxide such as tert-butyl peroxybenzoate [Perbutyl Z, manufactured by NOF CORPORATION, decomposition half-life 1 minute temperature: 170 ° C.] is selected. In order to ensure uniform graft copolymerization, the organic peroxide is introduced from a position where the amorphous polyolefin and the unsaturated carboxylic acid and / or their acid anhydrides are melt-kneaded and mixed with each other in the extruder. It is preferably metered.

During this period, the intermediate vent port is degassed under reduced pressure to remove unreacted unsaturated carboxylic acid and / or its acid anhydride. Deaeration is performed by using a vacuum pump with a trap and reducing the pressure to about 20 mmHg. In order to efficiently perform this removal, it is necessary to keep the system in a molten state. Generally, it is preferably 20 ° C. or higher, and about 120 to 220 ° C. from the softening point of the amorphous polyolefin.

(Neutralization step) Next, an ionic metal compound is supplied from a vent port after the acid denaturation zone,
The acid-modified amorphous polyolefin and the ionic metal compound are melt-kneaded. The ionic metal compound is generally in the form of powder, and is supplied from a tube provided vertically to the vent port using a quantitative feeder. The temperature of the melt-kneading zone of the acid-modified amorphous polyolefin and the ionic metal compound varies depending on the softening point of the acid-modified amorphous polyolefin and the type of the ionic metal compound, but is usually about 120 to 300 ° C.
It is. By this operation, the carboxylic acid group and / or carboxylic acid anhydride group of the acid-modified amorphous polyolefin is
Neutralized with ionic metal compounds. During this period, the vent closest to the die side is degassed under reduced pressure in order to remove water and the like produced as a byproduct of the neutralization reaction. Deaeration is performed by using a vacuum pump with a trap and reducing the pressure to about 20 mmHg. In order to efficiently perform this removal, it is necessary to keep the system in a molten state. Usually, the softening point of the acid-modified amorphous polyolefin is 20 ° C. or higher, about 120 to
220 ° C is preferred.

In the present invention, various additives, reinforcing materials and fillers such as heat resistance stabilizer, antioxidant, light stabilizer, antistatic agent, lubricant, nucleating agent, flame retardant, pigment or Dye, glass fiber, magnesium sulfate fiber (MO
S), zonotolite fiber, carbon fiber, calcium carbonate,
Calcium sulfate, barium sulfate, magnesium hydroxide,
Mica, talc, clay, etc. can be added.
The modified amorphous polyolefin of the present invention has flexibility,
It can be widely used as a packaging material excellent in adhesiveness, toughness, heat resistance, and pinhole resistance, a molding material, an adhesive, and a modifier for various resins.

[0023]

[Examples and Comparative Examples]

Example 1 Twin-screw extruder having cylinder blocks C _{0 to} C ₁₇ (Twin-screw extruder manufactured by Ube Industries, Ltd., inner diameter 55 mm, L / D =
60) was used. Amorphous propylene / butene-1 copolymer as amorphous polyolefin, Ubetac UT-
2780 [manufactured by Ube Lexen Co., Ltd., propylene content 71
Mol%, number average molecular weight 6500, heat of crystal fusion 7 Joule
/ G, softening point 110 ° C.] was melted to 150 ° C., and 10 kg / hour was supplied from an injection port provided in the cylinder block C ₀ . Further, molten maleic anhydride (Crystalman, manufactured by NOF CORPORATION) at 70 ° C. as an unsaturated carboxylic acid and perbutyl I (manufactured by NOF CORPORATION, tert-butylperoxyisopropyl monocarbonate) at room temperature as an organic peroxide. , Decomposition half-life 1 minute temperature: 155 ° C.) from the inlets provided in the cylinder blocks C ₀ and C ₃ , respectively,
The supply was 0.3 kg and 0.3 kg per hour, respectively. In addition, the vent provided in the cylinder block C ₁₁ is about 20 m.
The mixture was deaerated under reduced pressure to mHg to remove unreacted maleic anhydride.

Then, anhydrous zinc acetate was supplied at a rate of 0.15 kg / hour from a vent port provided in the cylinder block C ₁₂ . The C ₁₆ vent port closest to the die outlet side was directly connected to a vacuum pump and degassed under reduced pressure at 20 mmHg. A semi-transparent discharge product having rubber elasticity was obtained from the nozzle in the shape of a rod. The modified product thus obtained had an acid value of 20 mgKOH / g and a neutralization degree of 30%.
And absorption due to graft copolymerization with maleic anhydride to 0 cm ^-1 and 1720 cm ^-1, and absorption of maleic anhydride grafted copolymer to 1580 cm ^-1 is due to the neutralized structure Zn ⁺⁺ zinc acetate Was clearly observed, and it was found that maleic anhydride was graft-copolymerized to the present copolymer, and then 30% of the graft-copolymerized maleic anhydride was neutralized with Zn ⁺⁺ .

Using the obtained modified product, the tensile strength was measured by JI.
With SK7113, the melt viscosity (190 ° C)
Each was measured by a viscometer. In addition, nylon 6
Film (UBE nylon 1024B, thickness 50 μm)
The adhesive strength of Dooshi was measured. That is, the modified product is sandwiched between nylon 6 films, and the pressure is 5 kg / c at 160 ° C.
After hot pressing at m ² for 10 seconds, it was allowed to cool to room temperature.
The thickness of the adhesive (modified product) layer was about 50 μm. Then, this was cut into a width of 25 mm, and the T peel strength was measured at a tension rate of 200 mm / min in a constant temperature chamber of 23 ° C. Composition,
Table 1 shows the set temperature of the cylinder and the result.

Example 2 In Example 1, the amorphous polyolefin was changed to an amorphous propylene / ethylene copolymer, Ubetac UT-2585.
[Ube Lexen Co., Ltd., propylene content 80 mol%,
Number average molecular weight 6200, heat of fusion of crystal 12 Joule / g,
The softening point was set to 129 ° C.], and the same procedure as in Example 1 was performed. The results are shown in Table 1.

Example 3 In Example 1, the amorphous polyolefin was replaced by an amorphous propylene / ethylene copolymer, Ubetac UT-2280.
[Ube Lexen Co., Ltd., propylene content 95 mol%,
Number average molecular weight 6000, heat of fusion of crystal 15 Joule / g,
The softening point was changed to 146 ° C.] and the supply temperature was changed to change the organic peroxide to perbutyl Z (manufactured by NOF Corporation, tert-
Butyl peroxybenzoate, decomposition half-life 1 minute Temperature:
170 ° C.], the anhydrous zinc acetate was replaced with zinc oxide, the supply amount was changed, and the cylinder set temperature was changed.
Performed in the same manner as in Example 1. The results are shown in Table 1.

Example 4 In Example 3, the amorphous polyolefin was amorphous polypropylene, Ubetac UT-2115 [manufactured by Ube Lexen Co., Ltd., propylene content 100 mol%, number average molecular weight 3400, heat of fusion of crystal 18 Joule / g, softening point 152
C.] was performed in the same manner as in Example 3. The results are shown in Table 1.

[0029]

[Table 1]

Comparative Example 1 In Example 1, the amorphous propylene / butene-1 copolymer, Ubetac UT-2780 was not modified.
The physical properties were measured as they were in the same manner as in Example 1. Table 2 shows the results
Shown in

Comparative Example 2 The procedure of Example 1 was repeated except that the ionic metal compound was not supplied. Table 2 shows the results.

[0032]

[Table 2]

[0033]

INDUSTRIAL APPLICABILITY The acid-modified amorphous polyolefin of the present invention has excellent adhesiveness, toughness, heat resistance, and pinhole resistance in addition to flexibility, and is used as a packaging material, molding material, various adhesives, and modifiers. Can be widely used.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masaru Kunimura 3-10 Nakamiyakitamachi, Hirakata-shi, Osaka Ube Industries Ltd. Hirakata Research Laboratory (72) Inventor Yoshikazu Yamamoto 1980 Okiyama, Obe City, Ube, Yamaguchi Prefecture Address: Ube Industries, Ltd., Plastic Processing Machinery Laboratory (72) Iwa Tsuruya, Inventor, 2-3-11 Higashi-Shinagawa, Shinagawa-ku, Tokyo UBE Building 5F, Ube-Lexen Co., Ltd.

Claims (5)

[Claims] 1. A modified amorphous polyolefin obtained by partially or completely neutralizing a carboxylic acid group and / or a carboxylic acid anhydride group of an acid-modified amorphous polyolefin with an ionic metal compound. 2. The amorphous polyolefin of the acid-modified amorphous polyolefin contains 50% α-olefin having 3 to 8 carbon atoms.
The modified amorphous polyolefin according to claim 1, which is a polymer containing at least mol%. 3. An acid-modified amorphous polyolefin is obtained by adding an unsaturated carboxylic acid and / or an amorphous polyolefin to the amorphous polyolefin of claim 2.
The modified amorphous polyolefin according to claim 1, which is obtained by graft-copolymerizing the acid anhydride and has an acid value of 1 to 400 mgKOH / g. 4. The ionic metal compound is I of the periodic table,
The modified amorphous polyolefin according to claim 1, which is a compound of a metal having a valence of 1 to 3 of group II, III, IV-A and VIII. 5. An acid modification step of (1) converting the amorphous polyolefin of claim 2 into an acid modified amorphous polyolefin by an unsaturated carboxylic acid and / or its acid anhydride and an organic peroxide in an extruder. And (2) a neutralization step of partially or completely neutralizing the acid-modified amorphous polyolefin with an ionic metal compound, in succession, a continuous process for producing a modified amorphous polyolefin. .